Filtering system



Mamh 2% W35, R. B. RATHBUN FILTERING SYSTEM Filed July 11, 1932 6Sheets-Sheet 1 KNVENTOR fiasg Buxinnfidliun ATTORNEYS M NG March 26,1935. I

R. B. RATHBUN FILTERING SYSTEM Filed July 11, 1952 mliii 6 Shets-Sheet 2INVENTOR 4 ATTORNEYS March 26, 1935. R. B. RATHBUN 1,995,550

' FILT RmG SYSTEM Filed July 11, 1952 6 Sheets-Sheet 3 r v I H XWWWWW\WWH H I H H lNVENTOR F055 Baxian Zalhhrn Quwnpqw ATTORNEYS March 26, 1935.

R. B. RATHBUN FILTERING SYSTEM Filed July 11, 1932 ATTORNEYS March 26,1935. R. B. RATHBUN FiLTERING SYSTEM Filed,July 11, 1932 6 Sheets-Shee}.e

INVENOR Foss Bur/0J1 fill/E ihu ATTORNEYS or more separate nozzles.

Patented Mar. 26, 1935 UNITED STAT-ES 1,995,650 FILTERING SYSTEM RossBuxton Rathbun, American smelting El Paso, Tex., assignor to & RefiningCompany, New York, N. Y., a corporation of New Jersey Application July11, 1932, Serial No. 621,876

Claims.- (Cl. l83-57) The invention relates to the separation of solidsfrom fluids in which they are suspended, and more particularly to baghouses such as are used in connection with the smelting and refining ofmetals. 7*

According to one form of practicing the invention, the bag house may bemade up of a plurality of compartments, each compartment having aplurality of vertical bags therein. Extending along the ends of saidcompartments may be a lower inlet flue and an upper outlet fiue, theformer connecting with the lower, parts of said compartments and thelatter connecting with the upper parts of said compartments. A partitionis provided in each compartment separating the compartments into upperand lower parts with the bags extending through said partition.

' For removing the particles deposited on the inside surface of thebags, each bag may be provided with a rotary suction head Eachcompartment may be provided with a suction blower'for withdrawing thematerial deposited on the insides of I the bags. Each compartmentmayciufthermore be provided with a primary and secondary centrifugaldust collector receiving the discharge from the suction blower.

Arranged above the compartments may be a Gantry crane which may runlengthwise of the inlet and outlet flues. The crane may be providedwith,a carriage running lengthwise of the compartments for raising anyparticular bag for inspection or repair purposes.

If desired, each bag may be provided with a damper in the bottom thereoffor closing ofi that bag from filtering tion. Furthermore, the suctionapparatus of e 1 may be provided with a valve for closing off thesuction in that particular bag. These valves may be suitably operated byremote control, such as, by solenoids so that, if desired, the filteringaction of any one or more bags may be stopped and the cleaning action ofany one or more bags may be also controlled.

The invention alsoconsists in certain new and original features ofconstruction. and combinations of parts hereinafter set forth andclaimed.

Although 'the novel features which are be-- lieved tobechar'acteristicof this invention will be particularly pointed out. inthe claims ap-, pended hereto, the invention itself, as to its ob--jects and advantages, and the manner in which it may be carried out, maybe better understood. by referring to the following descriptiontaken incomprising one 'flllej21 which runs lengthwise of the bag house.

connection with the forming a part thereof, in which Fig. lrrepresents.a plan view of a bag hous according to the invention moved;

Fig. 2 is a section on the line 22 of Fig.'-1 showing the crane inposition;

Fig. 3 is a section on the line 33 of Fig.2 illustrating the relation ofthe bag compartments and the inlet and exhaust fines;

Fig.4 is a section on the line H of Fig. 1; Fig. 5 is a detailillustrating the construction of the centrifugal dust collectors;

Fig. 6 illustrates the construction of one or the bags;

Fig. 7 is bags; g

Fig. 8 is a detail of the apparatus onthe top of one of the bags;

Fig. 9 is a further one of the bags; 7

Fig. 10 is' an enlargedview illustrating the construction of the bag andassociated apparatus; 1

Fig. 11 is a section on the line 11-11 of Fig. 10; Fig. 12 is a detailof one of the suction nozzles taken on the line 1212 of Fig. 6;

Fig. 13 is a similar section taken on the line l3'-13 of Fig. 6; and

Figs. 14 and 15 are details of the filter mat. In the followingdescription and in the claims, various details will be identified byspecific names a plan view of the top of one of the detail of the upperpart of for convenience, but they are intended to be as .tails may bemodified in various respects without departure from the broad aspect ofthe invention.

Referring now to the drawings, and more particularly to Figs. 1-4, thebag house and asso ciated apparatus comprises a centrifugal blower,receiving the fmne laden gases from the metal accompanying drawings Iwith the crane relurgical process or other suitable source, from whichit is desired to recover the fume. This gas is fed in the direction ofthe arrows into the inlet Extending transversely from said inlet flueare a plurality of compartments 22 in which are located a plurality ofbags 23. The upper parts 124 of these compartments 22 connect with anoutlet flue 25 located above theinlet flue.21, as shown.

arated into a lower section 122 and an upper section 124 by a wall orpartition 123 which connects the lower parts of the bags 23 as shownespecially in Fig. 4.

A suitable discharge pipe, indicated by 26, is connected with the outletflue 25, which carries the cleaned gases to any desired point, such as,through treating apparatus or to waste.

It will be understood that the fume laden gases pass from the inlet flue21 into the sections 122, thence into the interior of the bags 23through the porous bags into the upper sections 124, thence into theoutlet flue 25.

Each bag is provided with cleaning apparatus for removing the fumedeposited on the inner walls thereof. This apparatus may comprise aplurality of suction heads 27 (Figs. 6 and 10) mounted upon a centralrotary pipe 28. Each compartment is provided with a suction main 29(Fig. 1) communicating with the suction heads 27 and leading to asuction pump 30 discharging into a primary centrifugal dust collector 31which is connected to a secondary dust collector 32. The discharge ofgas from the dust collector 32 is led by pipe 33 (Fig. 4) to any desiredpoint, such as, waste or it may be recycled back into the inlet flue 21.

The solids collected by the centrifugal dust collectors 31 and 32 may bedropped into a suitable container 34 from which any desired disposalmaybe made.

For controlling the supply of fume laden gas to each bag, a separatedamper 35 may be provided on the bottom of each bag, controlled by asuitable solenoid 36. For controlling the suction to each bag, aseparate suction damper 3'1 may be provided (Fig. 8) controlled by asuitable solenoid 38.

It will be understood that the building forming part of the presentsystem is constructed in the usual way with structural walls forming thefiues, compartments, etc. Located on the top of the building may be aGantry crane 39 running on suitable tracks 40. Located on the bridge ofthe crane may be a carriage 41 having suitable appa ratus 141 forlifting any bag 23 out of its compartment for repairing or otherpurposes, as indicated by A (Fig. 4) and as will be describedhereinafter more in detail. By the movement of the crane lengthwise ofthe fiues 21 and 25, and the movement of the carriage 41 lengthwise ofthe compartments 22, it will be understood that any bag in the buildingmay be treated.

Each bag 23 is supported by the top wall 42 of the building, asindicated particularly in Figs: 6, 9, and 10. Each bag is provided witha flanged collar 43 which rests upon the top wall 42 and whichcooperates with a seal 142 which may be made up principally of steelwool.

Each bag is made up of a plurality of stiff rods 45 suitably welded orotherwise secured to the top ring 43 and passing through holes in aplurality of fiat rings 44, as illustrated. The rods 45 are suitablysecured to a lower ring 46 at their lower ends.

Since the bag is supported at the top by a gas tight joint, provision ismade at the bottom for expansion of the bag. The lower part of the baghas an angular ring 4'7 connected to the ring 46 and a cylindricalsleeve ,48 connected to the ring 47. The sleeve 48 is adapted to slidewithin a seal 50 of steel wool or other suitable material containeo. ina holder 51 and mounted upon the parparticularly in Fig. 4. Eachcompartment is septition 123 which separates the upper and lowersections of the compartments.

It will be understood that the stiff wire rods 45 and flat rings 44 aresufficiently close together to provide a stiff rigid assembly to supporta filter mat 52 in accurate fixed position. This filter mat isillustrated in Figs. 14 and 15 and may be made as follows:

It may be made up'in the form of a cloth or fabric comprising a warp of,for example, #20 copper wire, indicated by 53, and a woof of the strandsof steel wool, indicated by 54.

Steel wool in ribbon form is available on the market in strips fourinches wide and about onequarter inch thick (unpressed) of any lengthdesired, with the fibres running substantially parallel.

According to the invention these strips are cut or pulled into stripsone-half the original width and rolled into strands about three-eighthsof an inch in diameter. These strands form the woof of the fabric, asabove described, and may be woven, by hand or otherwise, with the warpwires 53 into a mat. The warp wires may be spaced about three-quartersof an inch apart and stretched between nails driven into a board,

if desired, and the woof strands woven over and under in a manner wellknown in the art of weaving.

When the weaving is finished, the mat may be passed through tinnersrolls several times, which closes all the small interstices and coversthe warp wires 53 with a smooth surface of steel wool, the mat thentaking the appearance somewhat as indicated in Fig. 15.

This mat is secured to the inside surface of the cylinder made up of therods 45 by suitable attachment, such as, by fine wire loops at sum-,

ciently close points to properly support the mat.

It is better to mount the mat so that the rotary suction nozzles moveparallel to the strands of steel wool to prevent roughing up the mat,although satisfactory results have been obtained with the nozzle movingparallel to the warp wires.

As illustrated in Figs. 6 and 10, the central supporting nozzle stem 28may be made up of sections, the lower end being closed and supported inasuitable bearing 55 which in turn is supported by radial rods extendingthrough the adjacent walls of the bag.

At the top of the bag, the stem 28 passes through a plate 59 having asuitable seal 60. The plate 59 rests upon a collar 58 which in turnrests upon a plate '57 secured to the collar 43.

Keyed to the rotary stem 28 is a worm wheel 62 which rests upon a thrustbearing 61. Driving the worm wheel 62 is a worm 70 which in turn isdriven by gears 69 driven by a motor 68.

Mounted upon the plate 59 is a bracket 64 which supports a stationarypipe 65 to which is secured the stationary element o! a slip joint, theother part of which is secured to the stem 28. The stationary pipe 65 isprovided with a detachable connection 66 with branch pipe 67 secured tothe main suction pipe 29 (Fig. 1).

Also mounted on the bracket 64 is the solenoid 38 which operates thedamper 37 in the pipe 65, closing of! the suction to the suction head ofthe particular bag.

Thus it will be seen that by disconnecting the connection 66, the entirebag 23 and all associated apparatus may be lifted clear out of thecompartment by the crane 39.

Secured to the central rotary stem 28 are a plurality of separatesuction nozzles 27, Each nozzle 2'7 is made up of a cylindrical tube 71having its ends closed and provided with a longitudinal slot '74.Secured to the edges of this slot 74 are a pair of wide ears or flanges75 to prevent the suction nozzle from digging into the filter mat and tocut down suction leakage at this point.

Each cylindrical tube 71 is supported by an upper branch 71 and a lowerbranch '76, each of which is swiveled on corresponding branches '72 and73 respectively. Each lower branch 76 may be provided with a lever 77 towhich is connected a flexible strand 78 having a weight 79 and passingover branch 73 in such manner as to yieldably hold the suction nozzle 27against the wall of the bag.

It will be noted particularly from Fig. 6 that the suction nozzles areoppositely mounted and that each nozzle bears against a pair of flatrings 44 at its ends, these rings operating as tracks for the nozzles toprevent the nozzles from digging into the mat.

Referring now to Fig. 5, centrifugal separators 31 and 32 may besubstantially alike in construction so it is only necessary to describeone in detail. These separators form no part of the present inventionexcept in combination with the rest of the system,

The inlet to which the dust and gas are fed is,

indicated by 80 and is tangential to the circular body, as shown. Thefume laden gases are given a circular motion and they are caused totravel downwardly through the conical and cylindrical portions of theseparator, as shown, to the bottom. This action causes the solids todrop out of the bottom of the separator into a suitable container 34.

A valve arrangement comprising an upper valve 82, lower valve 84 andoperating mechanism 85 may be provided. The arrangement is such thatwhen valve 82 is open, valve 84 is closed. When both separators emptyinto the same container 34, the same operating mechanism 85 may alsooperate upper valve 82 of separator 32, if desired.

The treated gases containing relatively small amount of remaining solidparticles pass through the outlet 86 into the corresponding inlet 80 ofthe next separator 32 which operates in the same manner as the separatorabove described.

In operation, it will be understood that the fume laden gas is suppliedby the centrifugal blower 20 to the inlet flue 21, thence the gas passesto the lower ends of the bags 23 through the filter mat and out theoutlet flue'25. For cleaning the fume deposited on the inside of thebags, the suction nozzles 27 are rotated by the separate motors 68 andthe separate suction pumps 30 remove the deposited material, feeding itto the centrifugal separators 31 and 32 as above described. Therelatively clean gas discharged by the last separator 32 may be wastedor recycled back into the inlet flue. The solid particles collected bythe separators drop into the same receptacle or container 34 from whichthey may be disposed of as desired.

If desired, automatic clockwork (not shown) may be provided foroperating the several bag dampers 35 and suction dampers 3'7. Each bagin a compartment may be cleaned separately during which time its damper35 may be closed while the suction damper 37 will be open, it beingunderstood that all other suction dampers 37 of the same compartmentwill be closed and all other bag dampers 35 of the same compartmentwill, be open. In this way only one bag is out of commission forcleaning at a time.

For repairs it is only necessary to disconnect the suction pipe at thedetachable connection 66 and to disconnect the solenoid 36 from thedamper 35 after which the bag may be raised to the position indicated byA in Fig. 4, by the Gantry crane 39.

It is thought that the advantages of the present invention will beobvious from the description of the construction and operation abovegiven. The provision of weights 79 for yieldably holding the suctionheads against the back wall is excellent in that these weights are notaffected by changes in temperature. Furthermore, the rigid constructionof the bag frame properly supports the filter mat whose surface can bekept absolutely even with no depressions; and the wide lips on themouths of the suction heads prevent leakage at these points and inconnection with the tracks for the suction heads allow a close contactbetween suction heads and filter mat without any destructive digging in.

While certain novel features of the invention have been disclosed andare pointed out in the annexed claims, it will be understood thatvarious omissions, substitutions and changes may be made by thoseskilled in the art without departing from the spirit of the invention.

What is claimed is:

1. In a bag house, a plurality of bags, means for supplying fume ladengas to the interior of said bags, a separate gas supply valve for eachbag, a suction nozzle within each bag, a suction pump, a conduit passingout of each bag connecting said suction nozzle to said suction pump, anda separate valve in said conduit for each bag.

2. In a bag house, a plurality of bags closed at the top and open at thebottom, means for supplying fume laden gas at the bottom to the interiorof said bags, a separate valve at the bottom of each bag, a suctionnozzle within each bag, a suction pump, a conduit passing out of the topof each bag connecting said suction nozzle to said suction pump, aseparate valve in said conduit for each bag and a separate solenoid foroperating each valve.

3. In a bag house, a plurality of bag compartments, a plurality of bagsin each compartment, an inlet flue extending along the bag house, anoutlet flue also extending along the bag house, partitions in saidcompartments connecting the lower ends of said bags, conduits connectingsaid inlet flue with said compartments below said partions, conduitsconnecting said outlet flue with said compartments above saidpartitions, a suction apparatus disposed in the inside of each bag andpassing out through the top thereof said apparatus being movable overthe surface of each bag to remove deposited particles therefrom, a motoron the .top of each bag for driving said suction apparatus, a suctionpump for each compartment, a suction line for each compartment andextending from its particular suction pump to the bags of its particularcompartment, and separate detachable connections between thesuctionapparatus of said bags and said suction lines.

4. In a bag'house, a bag compartment, a unitary bag assembly thereincomprising a cylindrical filter, a pneumatic cleaning head therein,driving apparatus for said cleaning head, said cleaning head and drivingapparatus being unitarily supported with said filter, and means forremovably supporting said bag assembly in said compartment so that theentire assembly including cleaning head and driving apparatus may beremoved from said compartment as'a unit.

5. In a bag house, a bag compartment, a uni- 5 tary bag assembly thereincomprising a cylindrical open mesh framework, a filter medium within andsecured to said framework, a lower bearing secured to said framework, anupper bear- ROSS BUXTON RA'I'HBUN.

